It takes me a few min to get back to my cars normal idle

 

So ... what exactly is the question?

 

my idle is at around 1krpm and takes ages to go back to the normal 700

 

... and you’re wondering if this oil leak/seep, that appears to have been present for quite some time, may be the culprit?

 

I was just wondering if y’all think it’s a valve cover leak or not.

 

you definitely have some oil seepage, but that's not causing your idle issue.

one thing I would recommend is to change the clamp on the thermostat housing, might have coolant seepage there. those spring clamps lose tension after a while and can cause seepage and air can get sucked into the cooling system, the air in the cooling system can throw off the air/fuel ratio. as old as the 5th gens are I would recommend changing all the hose clamps in the cooling system. I was told those springs clamps are just used to speed things up on the assembly line.

 

What?

How does the cooling system affect air fuel mixture?

 

the coolant temperature sensor is one of the main things your ECU looks at to control the fuel ratio. if you get enough air in the cooling system your car will start running really rich even to the point where it can flood out at idle and be hard to restart.

 

So what do you think I should do ? I have literally no engine lights or nothing

 

change the hose clamp on your thermostat housing and change the valve cover gaskets. from what I remember reading the VQ30 has a different type of idle control. I have a 3.5 and it just uses a drive-by wire throttle to control idle. I have a 3.5 so I'm not sure exactly how the VQ30's idle control works, may be a valve.

does your car take a while to warm up? are you still running a thermostat inside the housing?